I am trying to generate 1/32" offsets from the attached  AcadR12 LT2 DXF file (Temp.dxf). The result I get is as shown in the attached BMP file (Offseterrors.bmp). It shows that the offsets are not continuous and are infact jumping from inside to outside. I have not had this problem before and just tried an older file and get the same unuseable result.

I know the lines are continuous ie the chain is not broken into separate segments or at least it is not broken in the DXF file, I verified this by taking the chain back into Acad and converting the line to a poly line.

I have not used LazyCam extensively but I have been able to get offsets to work in the past.

Mike

Sorry the attachments did not stay attached. I'll try again. Well that was not very succesful dont y'a love these intuitive proceeedures ! The software keeps telling me that I can't add the attachments because there is already an attachment by that name...which name #$%^&? I'll try them one at a time.

Well that was even less succesful.  Perhaps the files are already posted and I cannot see them. Can anyone help?

Mike

I'll try one more time to get the attachments to go along for the ride.

Mike

what version l-cam are you using?
what is the diameter of your part supose to be.i loaded it and the scale said the diameter is 0.1368
if that is the true diameter, a 0.03125  offset is way to fat.

bill

attached is a tap file using a 1/32 offset.
i used l-cam ver 2.02      it would load your dxf as 2 chains.
i tried l-cam 3.00 and 3.00.2 but it keep loading your file as 5 chains.

bill

The diameter is correct 0.1368. I don't understand your comment about the 0.03125 offset as being too "fat" I have other software that is quite happy with the file and generates the offset as it should (I have the parts to prove it). There is a small circle in the center of the drawing , it is 0.0625 dia and Lcam is quite happy to generate a 0.03125 offset on it.
The problem is that Lcam is breaking the continuous chain into many chains. My ver 3.00.2, down loaded two day ago just doesn't seem to like the DXF as generated by Acad, it is generating 20 chains on the DXF! Since my other software and Acad itself is confirming the the drawing is a continuous chain can Lcam be fixed to to do likewise? Is there a parameter to be set in Lcam? I tried the optimization connection tolerance but could not change it.

There does appear to be a difference between versions of Lcam that some how or other is not consistent in how the DXF file is interpreted. My current version appears to be looking at the file as it was as I was generating the outside chain ie Make a short section add another line and array the item around a central point.

Mike

Hey Mike,
I also have fresh version. I tried your dxf and got several chains too.
Changed the tolerance from .0001 to .001 and it shows as 2 chains. 1 inner and 1 outer.
I don't know why you can't change the tolerance, I just highlight it with a left mouse click and swipe then enter new value.
Good luck with yours,
RC

Thanks Rc and others.  I was about up load a bunch of tests I had done when I saw your message. Don't know why I couldn't change the tolerance earlier, I tried several times to no avail. Anyway the immediate problem is solved but... In the course of running tests I have found that as the size of my original outline is increased at some point in the increase Lcam all of a sudden changes inside offsets to outside offsets. Also in the larger version (4" dia) the outside offset is missing on one corner. I tried different tolerances down to 0.1000 and no improvement or change. Additionally changing "cut left" to "cut right" doesn't appear to do anything ie Lcam continues to cut either inside or outside.
I wonder why Lcam is so finicky about tolerances etc, I thought I read somewhere that Art was using a library for interpreting DXF formats. These inconsistencies do detract from an otherwise elegant piece of soiftware, hope they can be tamed.

Mike

mike
i mentioned the 1/32 might be fat from looking at the square corners compared to the size of the part .it just made me wonder if the size of the part l-cam was importing was a good number
and not a differant one.which has happened to me with my drawings.
changed my l-cam ver 3.00.2 tolerance to .001 from .0001 and got 2 chains.the toolpaths flip over too like yours.they will get it sorted out.

bill

I see in an earlier post with a different post heading that calling the DXF in and immediately generating an NC file without making changes and subsequently feeding that NC file back into Lcam that some problems go away. I tried this and it does behave a little better but I still have a problem of a small missing segment on the larger version of my original file. The missing segment or more exactly part of a segment is the last in the chain before the tool is adjusted for the next depth of cut. i wonder if the library file that the program compiler is referring to is faulty.

Bill, I was taking some liberties with the size of cutter in respect of the small indents but smaller end mills are hard to come and even easier to destroy! I've learned to live with 0.01575 radii fillets. I haven't noticed that Lcam has changed the sizes of any of my files but I haven't been using it very much, I find it is still to unpredictable and still has too many ways to make mistakes whereas my other software seems to accept some cruddy drawings and still manages to give a good tool path with far less input and setup.

I'm still hoping that Lcam will develop as Mach has and become a real neat handy package so I try the odd file once in a while.

Mike